WARSAW -- When executives from U.S. consumer-products maker Rubbermaid Inc. asked Lejb Fogelman to help launch Poland's first tender offer four years ago, he gave them his considered legal opinion: "It was crazy," the lawyer recalls.

Then he started figuring out how to do it.

At the time, there was no precedent for buying a company off the Warsaw Stock Exchange, and Poland's securities laws offered only vague...